//
// Copyright (C) 2004 OpenSim Ltd.
//
// SPDX-License-Identifier: LGPL-3.0-or-later
//

import inet.common.INETDefs;
import inet.common.packet.chunk.Chunk;
import inet.linklayer.common.MacAddress;
import inet.networklayer.contract.ipv4.Ipv4Address;

namespace inet;

//
// The list of practically important ARP opcodes
//
enum ArpOpcode
{

    ARP_REQUEST = 1;      // Request. RFC 826
    ARP_REPLY = 2;        // Reply. RFC 826, RFC 1868
    ARP_RARP_REQUEST = 3; // Request Reverse. RFC 903
    ARP_RARP_REPLY = 4;   // Reply Reverse. RFC 903
}

//
// ARP packet. This is a specialized version: prepared for IEEE 802 hardware
// addresses and IPv4. Packet fields are therefore represented by C++ classes
// MACAddress and IPv4Address. Also, some ARP protocol header fields are
// not modelled explicitly (their values are implied):
//   - hardwareType (not needed for modeling);
//   - protocol type (0x800 IPv4)
//   - hardware address length (6)
//   - protocol address length (4)
//
class ArpPacket extends FieldsChunk
{
    // ARP header length for IPv4 (4-byte addresses) and 802 LANs (6-byte MAC addrs)
    chunkLength = B(28);
    ArpOpcode opcode;
    MacAddress srcMacAddress;
    MacAddress destMacAddress;
    Ipv4Address srcIpAddress;
    Ipv4Address destIpAddress;
}

cplusplus(ArpPacket) {{
  public:
    virtual std::string str() const override;
}}
